Horizontal oil burner of the tray type



IFeb. 22, 1949. c. A. MILLR v HORIZONTAL `OIL BURNER OF THE TRAY TYPE Filed July 25, 1945 L I 3 1 A 4 Y T, M EM, E m f f/IIFIII l hlllllrllHNIllIHHhllHUl 0 2 FISA Feb. 22, 1949. c. A. MILLER HORIZONTAL OIL BURNER OF THE TRAY TYPE Filed July 25, 1945 NMS/5w Mmm/D" Feb.22, 1949. QAMILLER 2,462,529

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@f2/4 I I J2 .J /k FIB-'7 2/ FlE-IEI J2e. .3215-13 2 E?) JZ 2X F'IE-E f 'Z/a Ll o .i2 g o O rdf 1f 9 2 /O l/ .lfb/g O 3o g f O Z/a JJ k /fwf/vra/Z Patented Feb. 22, 1949 UNITED srArss HORIZONTAL OIL BURNER OF TH TRAY TYPE Clarence A. Miller, Petaluma, Calif., assigner to Kresiiy Mfg. Co., Inc., Petaluma, Calif., a cor; poration of California Application July 23, 1945, Serial No. 606,559

4 Claims.

This invention relates to liquid fuel burners, and particularly to oil burners of the vaporizng type for domestic and industrial use employing a gravity feed and from which the flame is projected in a horizontal rather than a vertical directon.

In the past, oil burners of this type have been subject to the excessive formation of carbon which ultimately effectively closed the orifices through which air is introduced into the combustion chamber. Furthermore, the creation of carbon upon the walls of the combustion chamber results in irregularities of the flow of air therethrough and the creation of turbulence which vresults in inefficient operation and incomplete consumption of the combustible vapors.

It is an object of the present invention to provde an oil burner of this type, in which the air is introduced into the combustion chamber in such a manner that complete combustion of all of the hydrocarbon fractions adjacent to the Walls of the chamber is obtained, with the resultant elimination of carbon deposits upon the walls.

Another object of this invention is to provide a burner of this type which produces an effective horizontal flame with the maximum effective combustion of the hydrocarbon fractions at a point remote from the flame throat or outlet.

Other objects of this invention will appear from the following description, in which the preferred embodiment of the invention is disclosed in conjunction with the accompanying drawings, in which:

Figure l is a plan view of an oil burner unit embodying the present invention.

Figure 2 is a side elevational view of the oil burner unit shown in Figure l.

Figure 3 is an enlarged longitudinal sectional View of the burner element incorporated in the burner unit, taken along the line 3-3 in Figure 4.

Figure 4 is a plan view of the lower casing section of the burner element.

Figure 5 is a lateral sectional view of the lower casing section, taken along the line 5-5 in Figure 4.

Figure 6 is a top View of the upper casing section of the burner element.

Figure 7 is a rear View of the upper casing section.

, Figure 8 is a front view of the upper casing section.

Figure 9 is a side View of the upper casing section.

Figure 10 is a bottom view of the upper casing section.

Referring now more particularly to Figures l and 2, there is shown an oil burner unit I0 embodying the features of the present invention Iand comprising a supporting plate II, carrying an oii burner housing I2 disposed on one side thereof and a motor operated fan i3 and associated oil supply regulator I4 disposed on the opposite side thereof. The burner housing I2 comprises wall structure, including a front wall I5, defining a housing for a' burner element 2i) disposed therein. The fan I3 is operative to supply air under pressure into the housing I2, which air' is utilized by the burner element 2B in a. manner more fully described hereinafter; while the regulator it is connected to a source of oil or other liquid fuel, not shown, and is operative to supply a regulated quantity of the oil to the burner element 2t. The burner unit IIJ is adapted to be supported in cooperative relation with a, stove, range, or the like, the housing I2 projecting into the firebox of the stove and the fan I3 and the regulator i4 being disposed exteriorly thereof.

As best shown in Figures 3 to 10 inclusive, the burner element 26| essentially comprises upper and lower casing sections 2| and 22 respectively, which are preferably cast from iron or the like. The two casings 2| and 22 are fitted together, as shown in Figure 3, and maintained in predetermined relationship by bolts or the like, not shown, which cooperate with holes 2|a and 22a respectively formed therein. The two casings 2| and 22, thus assembled, denne a combustion chamber 23, terminating in a rectangular throat 24 projecting through a cooperating opening formed in the front wall I5 of the housing I2. The casing 22 is provided with a depending well 25, into which oil is adapted to be fed from the regulator I4 in any suitable manner, as for example, by means of gravity. It is contemplated that in an average installation the oil will substantially ll the well 25 and at times form a thin layer in the bottom of an adjacent cavity 26.

The casing 22 is provided with upstanding walls 2l, 28 and 29, which are spaced from corresponding walls 30, 3| and 32 of casing 2|. At its forward end casing 22 is provided with a sloping wall 33, as shown, the forward lip 34 of which forms the lower lip of the flame-ejecting throat 24. The forward edges of walls 3i) and 32, together with the forward lip of an upper wall 35 of casing 2|, constitute the other lips of the flame throat 24.

I have provided various orices in the walls 30, 3|, 32 and 35 of casing 2i. Specifically, I have provided three rows of small orifices Sla in wall 3| of casing 2|, which orifices I refer to as primary orifices in that they serve` to admit air for primary combustion. Similar primary orifices 30a and 32a. are provided in side walls 3G and 32, respectively, adjacent to the lower edges thereof, substantially as shown. The purpose of the primary orices is to provide heated air and oxygen to the hot saturated vapors in the generally centrally located area within the combustion chamber 2.3. I do not propose that these orices admit suflicient air ,to provide complete combustion, it being the purpose of this lair to permit a slight degree of combustion and allow the gcneration of a smallV degree of heat. I do not wish the complete combustion of the hot Vaporized gases to occur in this area because such comh bustion would create a substantial quantity of carbon dioxide, resulting inthe dampening of further combustion in the forward portion of the combustion chamber 23.

VIt will be appreciated that the walls of the combustion chamber 23 will absorb considerable heat. I have found, for example, that in a small burner element 28 adaptable for use upon an ordinary kitchen range, the combustion chamber 23 of which is approximately four inches square and two inches deepwith the consumption of 32 cc. of oilrper minute, the walls will, within siX or seven Vminutes after the commencement of operf -ation of the device, acquire a temperature of ap proximately 7 00 F. This heat, when transmitted to therwell. and cavity 26, will result in the vaporization of the "oil therein and create a subs tantial vapor pressure moving directly upwardly I? Vtoward wall 35.

The introduction of primary airthrough the primary `orifices 3M, 3io, and will institute combustion and direct the fiow of saturated vapors generally toward the iiame `throat 2d. VIt will be appreciated that the air forced through Vorifices 30a, 3m and 32a `will have passed between walls E? and 33, 23 and 3|, and 29 and 32 and will have acquired con-- "siderable heat therefromthereby adding to the ycombustibility of the mixture,

'I have provided larger orifices 3l?) in wall 3! near the upper and side boundaries thereof, substantially as shown. Similar orices Sil?) and 32h `are provided along the forward sloping edges of walls 33 and 32, respectively. I have provided a like row of'secondary oriflcesb forthe admission of secondary airrthrough wall 35 at a peint immediately to the rear of the forward edge thereof. The purpose oforifices Sib in the end vwall 3l is to provide secondary air for the first v,stages of complete combustion within the corn- 'bustion chamber 23. Furthermore, air forced into the combustion chamber 23 through these zorifices gvcsthe heated gases their final direction and'creates a thin boundary layer of complete combustionalongwalls 3), 32 and 35. The introduction of substantial `quantitiees of air `through these orifices will thereby create a cushion vof completely burned gases immediately adjacent to the upper and side walls of the com bustion chamber 23 and prevent the formation of carbon thereon. The secondary orifices Sllb and 32h are adapted to provide a layer of imn rnetliately adjacentto the upper surface of sloping wall 33. The air introduced into the combustion chamber through these orifices is adapted toA mix with the rich gases moving forwardly immediatelyhover the oil pool in the well 25 below the combustion chamber 23 and to form a boundary layer of completely burned gases immediately adjacent to wall 33, whereby the formation of carbon therepn is prevented. The introduction of high veloc- ,Hi'ty air through the orices 35h is adapted to provide sufficient air for the complete combustion of the gases beyond the lips of the flame throat 25.

It will benoted that the primary air passes betweenfthe vertical walls of the lower casing 22 and Ythe vertical wallsY of the upper casing 2l before passing through orifices 30a, 3m and 320,.

It will beV seen that the primary air'enteing'the finest 'or"diseases beyend' #infested bu 'the combustion ena-mueres. frne'fmtrductin combustion chamber 23`does :sorat alhigher temperature than the secod'ryhy .entering the combustion chamber 2'3"'i`vhich 'has n'ot passed between the vertical walls but acquires its heat solely by the passage through` the orices 30h, Sib and 32h inthe vertical walls of casing 2|.

It will be appreciated that air will be supplied under pressure -by .the fan I3, and will be conducted to the burner element 2G from the surrounding housing lZ. As has previously been pointed out, all the walls of the burner element are heated to an elevated temperature and the air passed thereover and therethrough is likewise heated. The elevated temperature of the secondary air forceduthroiugh the orifices 30h, 3H) and '32h aids in the combustin 'of tliefsaturated vapors which haveprevi'ousl'y been 4r'riifx'ed zwliftht'lige primary air introduced throughforics 30a, L31u and 32a.

It is essential that the introduction of secondary air be restricted inasmuch as too 'great a quantity thereof would result in complete combustion within the combustion chamber :23. It is desired that `complete vcombstici'iy'andfiriaiiitemperature voccur at a point beyond 'the lips of the flame throat 24. y v K It will be noted that in "the design shwhlherein, the surface of the oil 'within the pool created in well 25 vand cavity 26 occupies Yvya relatively/small area'in the base of "casing22- v As I:the"casing122 asumes considerable heat, this roil ivaporiesand the gases expand throughout the, `cornbust-ion chamber-23. By the introductionefprimayand secondary airinto the pwardlymovng'hsaturated vapors in a predetermiiiedfmaner, I; can control the point of complete -cernlflstion olfthese gases.

The operation of `the 'oil burner unit lf'inay, briefly, be described as follows: The burnerfelement 2l) is connected to 'ja suitable T's'fupply "o`f' oil Vwhich is fed thereto frm'ftheyregulator"SM'by gravity or in anyco'riventional manner-,itbe'ing essential only that oil' be`continually"supplid'to the burner elementvZ 'and that the "same be 'maintained at substantially a "predetermined level which, as shown, is substantiallythatf of the lower surface of cavity`26. 'Air :is ""fedvtof the burner'element 23 from the housingllwhich lis supplied by the fan I3. VWhen the burnerun'it 20 and the oil in Well 25 areV cold, thesame may be lighted in any ceriventi'onal'rnanner. AfAse'o'rnbustion starts, the walls of'the-combus'tionchamber v23 gradually become" heated. As'has bee'n Ypreviously pointed-out, laftera'sl1`prt-period of operation'the walls -reachfa tempera'turefoffapproximately 700 F. YA" portion "'ff 'thehat "is 'transmitted' tor the y'oilih fvl'fellfZl `and tothef air entering the combustion chamber'23`thogh"jthe various orifices. Heatigfof theoil-iwell-Zf'and vcavity 26' results 'in the production vfof Pai-'substantial quantity of hot, saturated gas movingt ard wau'at. The introduction or primary-nettesten through orifices 3m shirts4 the'vapos'"mvingffr wardly and results in Vincorn'plete combustion. The introduction of primary air at apoint in ir'e- "immediatelyfover the oil pool.

The introduction of secondary air through-crigases forwardly through the throat 24. "The amount of secondaryV air' is Vp'redetermined toA provide Vs'uilcient "airfbr fc'orriplete VV'oiribu ln *of otwit-hin of secondary air immediately adjacent to the walls 3|), 3|, 32 and 33 provides a skin layer or boundary layer of completely burned gases which provide a suitable preventive cushion adjacent to these Walls to prevent the formation of carbon thereon.

My experiments have disclosed that the introduction of the proper amount of primary air is critical. 'I'he introduction of an excessive quantity of primary air is apt to result in the complete combustion of the hot saturated gases arising from the pool of oil which, in turn, results in the creation of substantial quantities of carbon dioxide and dampening of further combustion within the combustion chamber 23. The introduction of too little primary air would result in the generation of insufficient heat to heat the bottom casing 22 to the proper temperature to vaporize the oil in the pool or well 25. Also the introduction of too little primary air does not permit sufficient combustion of the gases in the central zone of the combustion chamber 23 and results in incomplete combustion of the gases along the walls of the same, regardless of the quantity of secondary air introduced. Incomplete combustion adjacent to the walls results in the creation of carbon; introduction of too little primary air does not create a forward movement of the mass of combustible vapors within the combustion chamber 23, with the result that when the gases mix with the secondary air excessive turbulence is created, thereby decreasing the efficient combustion of the mass.

Further experiments have shown that the introduction of too little secondary air results in incomplete combustion immediately adjacent to the walls of the combustion chamber 23 and permits the creation of carbon thereon, Introduction of too much secondary air through the orices in the rear of wall 3| of casing 2| results in complete combustion of all of the gases within the combustion chamber 2.3 instead of at a point beyond the throat 24.

By way of illustration, I have provided a combustion chamber 23 substantially 4 inches wide, 41/2 inches long, and substantially 21/4 inches deep. Primary air is introduced through thirty orices 3| a, each of which is 1A; inch in diameter, in the rear wall 3|, and ve orifices 30a and 32a of the same diameter in each of the respective side walls 3|) and 32. The rear-most of these oriiices 39a and 32a in the side walls 30 and 32 is in the same vertical plane as the forward wall of well '25. The lowermost of these orifices 3|a in the rear wall 3| `is approximately 3A; of an inch above the upper surface of the oil Within well 25, while the uppermost is approximately 11A; inches above that surface. It will be seen that a primary zone approximately lli inches high is created Within the combustion chamber 23, or, in other words, that substantially the entire lower half thereof consitutes a primary combustion zone. The primary air entering the combustion chamber 23 through these orices 30a, 3|a and 32al results in incomplete combustion of the gases within this zone and changes the course of the heated vapor from a vertical to a substantially horizontal course.

Secondary air is provided for the combustion chamber 23 through twenty-one orifices 3|b, each of which is approximately of an inch in diameter, adjacent to the lower surface of wall 3| and by the provision of two more groups of three orifices 3|b of the same diameter in the wall 3| respectively adjacent to the inner surface of walls 30 and 32. Introduction of secondary air through these orifices 3|b creates a zone of complete combustion immediately adjacent to these walls, with a zone of incomplete combustion between said zone and the primary zone, and further aids in the forcing of the gases in a forward direction.

Secondary air is further provided through three orices 30h and 32h of the same diameter in each of the respective Walls 30 and 32 immediately adjacent to the sloping wall 33. Secondary air introduced there further supplies air for a zone of combustion immediately adjacent to the sloping wall 33 and for complete combustion at a point beyond the throat 24. Further, secondary air is provided by sixteen orifices 3512 of the same.

size in wall 35 immediately adjacent to the throat 25. The air introduced at this point is calculated to be sufcient to result in complete combustion of the gases at a point beyond the throat 24.

It will be appreciated that the number and size of the orifices may be varied for different sizes of combustion chambers. However, I have found that it is desirable to provide a lower zone of primary combustion and a surrounding zone of secondary combustion, which latter zone is likewise divided into a zone of complete combustion immediately adjacent to thewalls of the chamber and a second zone of incomplete combustion to which further secondary air is added immediately adjacent to the throat 24 in order that complete combustion of all of the gases will gccur at a point beyond the combustion chamber While there has been described what is at present considered to be the preferred embodiment of the invention, it will be understood that various modifications may be made therein and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. A burner comprising upper and lower casing sections secured together and defining a combustion chamber, said upper casing section including a top wall and a connecting downwardly extending first skirt having an opening in the front portion thereof, said lower casing section including a bottom wall having a depression formed therein defining a liquid fuel reservoir disposed below and directly communieating with said combustion chamber and an upwardly sloping front wall and a connecting upwardly extending second skirt, said first skirt extending above and having its lpwer part arranged within said second skirt in spaced relation thereto, the front edge of said top wall andthe front edges of said first skirt adjacent to the opening in the front portion thereof cooperating with the front edge of said front wall to dene a forwardly directed flame outlet throat, means for supplying liquid fuel to said reservoir, said first skirt having a number of air inlet openings formed therein and disposed above and below the upper edge of said second skirt, and means for directing air from the exterior of said casing sections through said openings and across said reservoir, whereby vaporized fuel from said reservoir and flames of burning fuel in said combustion chamber are projected forwardly through said flame throat to the exterior of said casing sections.

2. A burner comprising upper and lower casing sections secured together and defining a combustion chamber, said upper casing section including a top Wall and a connecting downwardly extending first skirt having an opening in the front por .within said second skirt 7 "tion thereof, said lower casing section including a bottom wall :having a depression formed thereindening `afliquid fuel reservoir disposed below and directly communicating with said combustion chamber and an upwardly sloping front wall .fand `a connecting upwardly extending second skirt, Vsaid first skirt `extending above 'and having its lower` part arranged Within said seco-nd. skirt v@in spaced relation' thereto, the front edge fof said .top wall and the front edges of said first skirt adi fjacent'to the opening inthe frontportion thereof cooperating with the front `edge of said front Wall 'to define a forwardly directed flame outlet throat, :means for supplying liquid fuel to said reservoir, said first skirt having `primary and secondary air Y- inlet openings formed therein and respectively .disposed below and above the upper edge of said second skirt and said top wall having secondary .'airk inlet 'openings formed therein adjacent-to the v`front edge thereof, and means for directing' air :from the exterior of said casing sections into said primary air inlet openings and into said secondary air vinlet openings, `the air directed into said vprimary 'openings sweeping across said reservoir,

-Ywhereby vaporized fuel from said reservoir par 4tiallyhurned in said combustion chamber', the air directed into said secondary openings entering directly into said combustion chamber whereby yvaporizeol fuel is further burned therein and .flames Yof burning fuel in said combustion vchamber are projected forwardly vtherefrom through said dame throat to the exterior of said `casing sections in order to burn completely the -Vaporized fuel exteriorly of said casing sections.

3. A burner comprising a housing,.upper and lower casing sections arranged withinsaid housing and Asecured together and dening a combus- Lti'on chamber, said upper casing section including a top wall and a connecting downwardly extend- Aing first skirt having an opening inthe front portion thereof, said lower casing section including a bottom vwall having a depression formed therein ."dening a liquid fuel reservoir disposed below and directly communicating with said combustion chamber and a front wall and a connecting up- 8 formed-thereinand disposedsabove andbelow the upper edge iof said second skirt, and m'eans for supplying air into 'said housing, whereby :air is directedifrom within said "housing through said air Ainlet vopenings and across said' reservoir, whereby vaporized fuel from said reservoir and flames-of burningfuel in lsaid combustioncham- -ber are projected forwardly lthrough saidame throat to zthe exterior of said housing.

4. A burner adapted to project a flame'horizontally-therefrom comprising upper ,and lower casing :sections secured `together and defining a combustioncharnber, said 'upper casing section including :a top Wall anda connecting downwardly ex.- tending first skirt having an opening in the front portion thereof, said lower casingsection in- Vcludinga bottom wall and a connecting v.upwardly Aextending second skirt, said rst skirt extending `above-and having its lower part arranged `within said second skirt'in spaced relation thereto, :the front edgeo'f said topwall and the front edges of said first skirt-adj acent tothe opening in the v,front portion thereof cooperating with .thefront edges of said second skirt-and bottom wall of said lower casing section -to denne a forwardly directed vflame outlet throat, means tosupply liquidfuel to said bottom ywall of -said vlower casing, said first skirt having a number of air inlet openings 'formed therein and arranged above and below .the upper edge -of said second-skirt, and `means for directing air 'ffrom the exterior lof said casing sections through n said air inlet `openings Vand into said combustion chamber whereby vaporized fuel and iframes of burninglfuel in said chamber are lprojected forwardly through said flame throat vto the exterior ofsaidcasing sections.

CLARENCE A. MILLER.

'REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 'Number Name Date 1,530,079 Hood Mar. 17, 1925 1,660,106 Stroud Feb.`21, 1928 '1,912,713 Kreeky June '6, `1933 .2,290,544 DeLan'cey July 21, 1942 2,369,833 Livar Feb.`20, 1945 2,391,585 Miller Dec. 25, 1945 FOREIGN PATENTS 'Number Country Date 358,041 Great'Britain Oct, 2, 1931 418,414 'Great Britain Oct. 24, 1934 

